I love to DP my BTs... but there is a problem.
You see, the EC can't be held in reserve before the game to allow him to catch a ride in a DP. You can find the whole argument over on BolterandChainsword.com, but to summarize, he can't ride in a DP as of now.
With a DPing BT force, I try to cut the cost of my units to alleviate the problems of the single special weapon (i.e. I run 7 initiates and 3 neophytes). This costs me 193 points with 7 initiates w/bolters, 1 PF & 1 PG, and 3 neophytes w/BP/CCW in a DP. I usually take at least 4 if I'm trying to DP, and let the EC walk =). The initial drop isn't as damaging as it is with regular marines w/2 special weapons, but it still brings fear into my enemies. Plus, you can shave off even more points if you need to by using more neophytes. The neophytes add a bit of CC punch, while the bolter marines open a can up on infantry. The PF prevents being stuck against a wraithlord or something. Basically, you fall, fire, and get shot back, getting sucked into combat with your RZ move.
And as for the RZ move, we aren't Khorne. We just don't run after vehicles. In every tournament I played, the RZ was a necessary check after 1+ casualty that allowed you to move up to the distance rolled on the d6 towards the nearest visible because of it being just like a massacre move (and no one I've played makes you move the full distance on the massacre move). So if the nearest is a rhino in a place you don't want to go, then you just move 0". The penalty of taking a morale check after every casualty counters the possible advantage of RZing (hence the necessity of a well-protected Marshal in a BT list).
I have yet to play a straight mech BT list. I get a bad feeling from rhinos simply because I play tau too, and I have never had an opponent's rhino make it past turn two; although, sometimes by turn two their job was done anyway, so it didn't matter. Rhinos aren't bad, but I'm more of a heavy tank guy, so I'm building my 3rd LRC as we speak (well, not now, but when I'm done typing). My friends don't play apoc, but we do play no-point, full FOC battles, so I don't get to play all my models very often. And one friend has a full FOC of IG anyway, so I don't get to do much very often. I have a full FOC of tau, too, but it isn't fun to play against yourself. But in any case, it's about 4500 points +/-, and I might try to run a full FOC list like:
Marshal w/command in DP
Chaplain w/command in DP
EC (in LRC)
5 Termies w/2 AC in DP
5 Termies w/2 AC in DP
5 Termies w/2 AC in DP
10 Bolter Marines in DP (PG/PF)
10 Bolter Marines in DP (PG/PF)
10 Bolter Marines in DP (PG/PF)
14 CC Marines in LRC (MG/PF)
15 CC Marines in LRC (MG/PF)
15 CC Marines in LRC (MG/PF)
10 Jump Marines (2 PP/2 Shields/PF)
10 Jump Marines (2 PP/2 Shields/PF)
10 Jump Marines (2 Flamers/PW)
Vindi
3 Las Pred
3 Las Pred