I've bought a couple pieces from them and it was fine. They def end up being on the expensive side due to a) an initial high price as compared to private sellers, plus b)sales tax and more recently c) very high flat rate shipping.
I tried to buy the B&W sub they've had listed on and off since February last week. It's an expensive, odd ball sub that is only controlled via a B&W app which could lose support at anytime as B&W has changed hands every few years over the last decade. They slightly discounted it and insisted on charging $400 for shipping from CO to me in NY. I'd just sold and shipped two similar sized and heavier JL subs further west of CO for $130 each- insured. The $399 they were charging was absurd. Flat rate, when its hugely above actual cost isn't a fair model in my opinion. The combo of the 8% sales tax which was about $260 plus the unnecessary additional shipping cost of $270 on top of the actual $130 shipping cost made the purchase over $600 more than it should have been. I bought a pair of REL s812 from USaudiomart and moved on. Days later I saw that TMR marked down the B&W sub slightly again. Had they just moved another few hundred dollars on the total price for me it would have been in my living room instead of still in stock and being marked down. I also felt the salesman I was working with had no decision making power and was taking hours between emails to get back to me after having to check with someone on every question. It gave me plenty of time to continue to look elsewhere and ultimately buy the REL (with no tax, competitive shipping and fast transaction process).