Nexus 4 + T-Mobile USA

So some of my math has me really considering the Nexus 4 along with a T-Mobile SIM. I'm hoping any T-Mobile employees or anyone that's a current T-Mo customer can lend some verification to my math.

Here's my current situation:

Carrier: Sprint
Handset: HTC EVO 4G (on CM7.2 right now)
Contract: June 2010 to June 2012 (free to go, basically)
Monthly Bill: ~$87 ($69.99 plan, surcharges/fees/taxes, $10 Premium Data, $8 equipment insurance, 15% discount)
Plan Details: 450 min / UNL SMS / UNL DATA

I don't call (avg 73 min/month), I text a lot, and I've been under 2GB of data usage every month except for one time when I went up to 2.1GB. I was originally planning on going back to AT&T for HSPA+ and LTE (CDMA is the worst thing ever created) and found that the wife and I could do Mobile Share for $75 each for UNL min / UNL SMS / 4GB SHARED / WIFI TETHER.

Cue the reason I still have my EVO 4G: the Nexus 4 arrives. I don't like LG's previous phones, but I really want to be on the latest Nexus. My Nexus 7 has me spoiled about getting quick updates. So I just poked around T-Mobile's website and found an interesting plan:

Contract: No Commitment, None, Nada, Zip, Zilch, Nil
Monthly Bill: $30.00
Plan Details: 100 min / UNL SMS / UNL DATA

So now I'm considering grabbing a 16GB Nexus 4 for $349 and just getting a SIM from T-Mo... with no contract and probably at least 2 weeks to say "nah, forget it". Still, I could hop on to AT&T at anytime in the future with the same device (pentaband!). Still won't have LTE, but I've seen proof of AT&T's HSPA+ workload drop severely now that the iPhone 5 has arrived.

My only two concerns are:

1) Will I miss LTE that much? Probably not.
2) Will T-Mo's network piss me off? Unknown, but it's worth a shot and I really don't have much to lose.