If you want to use a dynamic, and stay under $400, I'd go with either the Shure SM7B (just bought one) or the Sennheiser/Telefunken MD421. Great sounding solid mics and about $100 less than the RE20!
If you want an EV then the RE27 is better than the RE20. IMO the EV's are better paper weights than mics. Charlie Van dyke uses the RE20... like he needs more low end, lol!
Condensers? I like the RODE NT2, which is no longer made but readily available on eBay. It's a great condenser for under $300-350. It's open on the top end, but has nice low end. If you can't afford a TLM 103, get the RODE NT2.
Tube mic?
The RODE NTK tube can be had for under $500 new. Solid tube mic. Great warmth and texture.
Paired with the Symetrix 528e it sounds pretty good. Local cable company I do VO for has this combo (and a nice whisper booth). Sounds great.
I have no experience with the Studio Projects line. But have heard some positive reviews. As for it sounding like a u87? Wow. That's a bold statement. Then again, are we talking the current u87's being made (which suck) or a "vintage" u87? I'd go with a TLM103 over a u87. All you're doing is paying $1000 more for multi patterns that as a VO you just don't need. Just an opinion.
Mic pre's... I have a dBX286a in line with a UREI 1176LN. Great combo. Don't usually use the dBX on it's own. I know that "BC" (the big voice) uses the 286 with a RE27. Then again, he's got a helluva voice.
I personally prefer the older Symetrix 528 to the 528e. Better quality parts. Any engineer will tell you that if the two are opened up and A/B'd. Again, eBay is a great resource. Just be sure to buy from someone with over 98% rating.
A Valley 400 (not the 401) is another vintage mic pre that can be had inexpensively. Chris Corley used that pre (with Sennheiser 416) for years before moving on to the Maney VoxBox/RODE II Classic combo.
And for about $175 you can get the FMR RNC (Really Nice Compressor) mic pre
http://mercenary.com/realniccom.html
I use the Echo Mia card. Great for $140. Eventually I'd like to move up to a Card D for XLR I/O.
One more inexpensive tube mic pre that's pretty good is the SM Pro TB101
http://www.samash.com/catalog/showitem.asp?ItemID=33323