Do Slot loading Transports have sonic Advantages

No they don't, most transports are made of plastic, and some cheesy plastic clamping system. If you want a good transport system you have to search for well made ones ...Like the Esoteric Verdes Neo drive is an example of how good a transport can get...there are others too.The goods ones use Aluminum or a combanation of plastic and aluminum. Slot loading means nothing as to the quality of the drive. The best drives I have seen use a drawer. I am not seeing any trend you speak of for slot loaders.

As mentioned above, apart from the drives made by Esoteric, most of the slot mechanisms are nothing special. Most are cheap CD ROM drives. I think cheap is the primary "driver" of the choices made by manufacturers, and perhaps, availability.

I think its fair to say that its probably more important to take in the design of the slot load transport, as opposed to it just being a slot loader.