I have a Sima CT-2 and while it does what it's designed to(I've never ran across anything, including BD, that it wouldn't let me copy) it's drawback is it lightens the picture. I have 3 and I'd say one lightens ~+7.5 IRE while the other two are even worse(I'd guess +15 IRE). They also run a bit warm so I always unplug them when not in use. I believe the Sima is also long gone new and only available used.
I haven't hear anything bad about the Video Filter brand but it is the most expensive of the filters and I don't think it's made anymore, I've never used one.
I've heard mixed results with the Grex and Copiall, I'd guess they may be similar in quality as the Sima but haven't used one.
I believe the MCM filter is only for VHS or DVD without as strong CP, for sure not BD. The MCM is the cheapest but I'd only use it with VHS.
If I had it to do over I'd purchase the AVT 8710 TBC. It has picture quality adjustments so it should not lighten or darken the picture and it could also be used to correct the picture of a badly mastered source. Someone not too long ago posted a link to a company that sold the AVT 8710 for <$200($187 I think) but no one had really heard of them so I was a bit leery to give them my CC#. The going price from major retailers like B&H seems to be ~$230 but if you only wanted one device I'd probably suggest it.
I think the other TBC your talking about is more a professional product and priced accordingly, ~$500 I think.
My guess is the TBC 1000 is a real quality product but I like the picture quality adjustments the AVT 8710 has, besides being 1/2 the price, so thats the one I'd go with.