Slot, tray, or top load?

Any thoughts on the inherent advantages/disadvantages between CD loading mechanisms? Between slot, tray, and top loaded CD transports/players, which do you consider the best and why?

I prefer top load (I don’t have one, but would prefer it). The obvious reason: Fewer parts to fail than the other two. Wish I had one.
I have a top loader. Love it. Love the simplicity. However, it does require extra space, so it may not work on your audio shelf, unless you have a tall opening or sit it on the top. If you have the room, top loaders are great.
The Sony SCD-1 is a top loader using a sliding top door.

I like it because the disc is not moved -- I place it on the spindle by hand and the door closes over it.  No need for any extra mechanism to move the disc into position.  I think it is more reliable and less risky of disc damage.

However, the top loading architecture requires upper clearance, and I have always had to locate the player on a top shelf.
None of the above. As someone whose CD transport is aged and limping along but also as someone who has recently entered the wonderful world of streaming I’d never buy another dedicated CD transport/player, and my next move is to buy something like one of the Innuos Zen streamers. They have onboard CD drives and internal storage to make it a breeze to rip all my CDs and can stream from my Qobuz service so I have access to all my music in any way/order I want to play it along with thousands of titles I don’t own. After experiencing streaming, being limited to playing individual CDs seems fairly absurd — kind of like having to reach into my pocket for change to throw into a toll basket. Ain’t no going back for me. Sorry I didn’t answer your question directly, but FWIW.
I owned the top-loading McCormack Digital Drive SST-1 for quite awhile and while I have no idea if there’s any sonic advantage, the act of setting the CD into place, putting the magnetic puck on top and sliding the cover shut was a much more satisfying experience than pushing a button, dropping a CD onto the tray and pushing the button again.
Like Soix said, ripping the music to files is the way forward, along with music files that are downloaded.
Asking a question about which type of CD player and getting answers favoring streaming is like being on a car forum and someone asks which brand of clutch plates work best for a certain situation and some of the answers say to get a car with an automatic.

All the best,
I've own/owned all of them.  I prefer the top load of my CEC.  Never liked the slot load.  I was always afraid that it would somehow scratch a CD, (it never did), like my car CD player was prone to.

I agree that you do need extra clearance for the top loaders.
I had one top loader, the Rega Apollo.  It was a slow, finicky machine that rejected many discs as unreadable that played just fine on other players.  I have no idea if the top loading had anything to do with it, but I was glad when I got rid of it
+1 @nonoise 
the question was not about CD vs streaming.  No need to evangelise about the joys of streaming on an unrelated thread. 

Toploading for me, although a manual closing tray like Naim do, is a good compromise if you don’t want the CDP atop the rack. 
I brought up streaming as someone who was reluctant but who recently adopted streaming in the event the OP hadn’t thought much about it or what it might add to his/her listening enjoyment and how easy and painless it can be.  The OP can just disregard if they have no interest in streaming, but I don’t think bringing up other potential options an OP may not have considered is inappropriate in the least and can frequently be helpful and informative.  I know people have brought up solutions I hadn’t thought about in some of my posts and I greatly appreciated the information. 

That said, I’ve had three CD players/transports and all had front-loading drawer mechanisms.  Two of the three developed drawer problems so you can put me in the top-loading camp as well.  But even given my past experience, sound quality/characteristics would still be by far my overriding #1 priority. 
I have a vinyl rig too.  Do you want to tell me I should be streaming instead of spinning? lol
I don't know what soix would say, but having both vinyl & digital front ends myself, I definitely recommend you start streaming asap... Not as nice looking as a top-notch TT-arm-cartridge setup, but the hi-end digital front ends sure perform well, comparable to the analogue in fact!
And it's very simple to stream or download music nowadays!
(TT is a Simon Yorke pluto arm, old fm acoustics phono).

I think the real question is: What unit will be the most reliable and best SQ? While I think the top loader has the coolness factor and potentially fewer mechanical problems, tray style is probably the most common and there are many very good versions of it. I ended up buying a slot loader because of reviews and I like how clean the face looks. It's been rock solid dependable thus far.
Sorry, but my internet is unreliable.

For example, my Spectrum TV streaming app stopped working with my Roku recently. Used to be OK, but I couldn’t use it to watch the Super Bowl. Total fail.

I hope your music streaming should remain troublefree.