Ivan Clearwater
Interesting. So I forfeit my transports, and I'm allowed to deepstrike my units? Where ever I want?
Well you don't "forfeit" your transports, you just don't get them at all for any Grey Knight-related squad. The only people who get transports are the Inquisitorial people, i.e. Stormtroopers and Inquisitors and their retinues.
However, if you'd still like to move those Grey Knights quicker, you can purchase a Land Raider and then have them embark/disembark wherever you want. The LR isn't taken as a transport option but that doesn't mean you can't put guys in it.
Also, while yes deepstriking tends to get you shot at a lot (since no one likes Grey Knights in assault range) you just have to use them tactically. My Teleport Attacks and deepstriking terminators have faired pretty well when deepstriking for the most part. IF anything, they are a big 'ol damage sponge for that turn. Though quite frankly, I still like a 10 man squad of Grey Knights with incinerators deepstriking into an enemy army. It really throws off my opponents plans because suddenly there's 8 stormbolters, 2 flamer templates, mixed with one big-a** deadly close combat squad right in the middle of their army. Yeah, they might die, but on the other hand, in your shooting phase they'll no doubt make back quite a bit of their points in kills and absorbed fire that could've been pointed at my Grand Master or Land Raider. So I dunno, once again it's a lot about the luck of the roll on how effective they can be.