Hi Doug. If you are thinking of the Hales, the T8s are in another league from the T5s. Even though they share the same tweeter and midrange, they are much different sounding. The T5s have a single stock 10" paper cone woofer and the T8s have two custom made proprietary aluminum 10" woofers [made by Alumapro to Paul Hales specs].
Before discussing the sonics, I will tell you that I blew a tweeter in my T8s just this last Sunday. What did I do? Popped in another voice coil in 20 minutes [and I am no techician or whiz with a soldering iron at all!] I mention this because replacement drivers/ parts are readily available. Although I do have an entire extra tweeter and woofer, I also have two extra tweeter voice coils [which is the only part to go when a tweeter blows]. The tweeter voice coils are $22.00 a piece from Madisound and the entire woofers are available for $130.00. The midrange drivers are readily available also and are the same as those used in the Coincident Super Eclipses.
Sonically, everything I say is based on MY system, MY room, MY tastes and prefernces in music and MY ears (feeble as they may be). With all due respect to the previous poster, I find the T8s one of the best speakers on the market at ANY price! As a reviewer, I have had the privilege of hearing many speakers in my room. There are so many great choices for the music lover and audiophile these days at all prices, we have never had it so good. For me, I prefer the T8s becuase they do everything very well and are so seamlessly balanced throughout the frequency spectrum. They are VERY revealing and transparent, disappear for a large speaker and can do both macro and micro dynamics as well as anything I have heard. They are sealed enclosure so the bass is NOT mushy or overdamped and, with those two 10" woofers and good placement, capable of the some of the best bass I have ever heard - full, deep, taught and accurate without being bloated. BUT, the previous poster is hitting at one good point - they are difficult to drive and need enough power/current. You need either very good solid state [I use the 100 (more like 140) watt Lamm M1.1 hybrids and I'm very happy] or powerful tubes like the Wolcott Presence or the powerful VTLs to make them sing. They WILL reveal weakness upstream.
Can you better them in certain areas? Possibly, but it will likely cost you a lot more and you may give up other things to get it. I listen to many differnt types of music ranging from butt-kickin, driving 70s soul/funk bands like Tower of Power (which I listen to at real world volumes) to acoustic jazz, to pop, to folk music to large scale orchestral works. For this reason, I have not found anything that can do them all so well and do it with such a balance of strengths.
Finally, because at first when Hales went out of business, I was worried about replacemnt drivers, I went through a phase where I was trying to find a speaker to replace my beloved T8s. After a frustrating 10 months of trying and failing, I just kept coming back to these speakers for all they do so well. They have now been in my sytem for 3 years - longer than anything else [which, for a reveiwer who gets to try so much for such great prices, says a lot].
I do also have stats [Inner Sound Eros] and minmonitors by Silverline, which I enjoy at different times, but the T8s occupy my main room and are what I use for my most serious listening sessions.
I hope this helps.