OK, since a few people have been asking, here's a detailed comparison of Tocil vs Cryfield:
Let Length: 30 weeks £83/week for Cryfield, 39 weeks for Tocil. Really a matter of personal preference, this. Personally, I prefer the flexibility of the 39 week let, but it is significantly cheaper to go for the 30 week let.
Cost: £83/week, £105/week for Tocil. Obviously, Cryfield is cheaper on a weekly basis as well, so that's a win there.
Room facilities/size: Cryfield has a sink (with mirror and light, but no shaver port) in the room, which Tocil lacks, Tocil (or at least my room, I'm not sure how universal it is) has significantly larger desks, which I found useful, but does take up a lot of space. Both have plentiful supplies of power sockets. Al other facilities are identical. The Tocil rooms feel bigger inside, probably due to being more square. I'd say a win for Cryfield, overall.
Kitchen size: I had a kitchen with 12 rooms assigned to it in both, so this is a fair comparison. The kitchen in Cryfield was significantly larger, easily twice the size. Definite win for Cryfield there, though I'm not sure how this scales to the smaller kitchens in Tocil.
Kitchen facilities: Cryfield has one large fridge, one large freezer, two microwaves, two sinks, a toaster, one oven (with hob) and an extra hob. Tocil has two large fridges, one large freezer, two full ovens (better ones than in Cryfield) and two sinks (sharing a tap, rather than separate as in Cryfield). Definite win for Tocil.
Kitchen storage space: Tocil had one large-ish cupboard each (approximately: some people will have one large and two small, for example), with no drawers. Not really adequate (I ended up storing stuff in the fridge just because that was where I had space). Cryfield has two large-ish cupboards each (approximately, as above), and also roughly one drawer each. Plentiful, and a definite win for Cryfield here.
Overall layout: Tocil is flats, Cryfield corridors. Personally, I find corridors more convenient, but this is really a matter of personal preference. Both have fairly narrow corridors to get around. Cryfield also has a communal seating area at the entrance, which is nice. Conditional win for Cryfield.
Toilet/Shower/Bath facilities: My flat in Tocil had two toilet/shower rooms and one toilet/bath (with no shower above it, so mostly useless) room. (NB: I'm led to believe that this wasn't typical, and other flats had an extra shower and no bath). My half of the floor of Cryfield (shared between 25 people) has 2 shower/baths, 5 showers and 5 toilets (all separately lockable, which is far better). That's comparable ratios, but Cryfield has four advantages here: (1) Since they're all separately lockable, you don't have problems where you can't use one thing because somebody else is using something else that happens to be in the same room; (2) since the Cryfield ones are bigger groups shared by more people, they're less likely to be all filled at once; (3) since it's in corridors, if all of the ones in your area are full, you can just go to the other side of the floor/upstairs/wherever; and (4) since the baths in Cryfield actually have shower heads/curtains, they're actually useful a lot more than the Tocil ones are.
Location: Tocil is very central, pretty much exactly between Tescos, the SU and the main academic buildings. The area is fairly nice, backing onto a stream and some grassy/woodland areas, but is next to some building work at the moment which, in the almost inevitable event that it overruns into term time, might make a bit of noise. Cryfield is over to the side, closer to the WBS building and close to the SU, but further from everything else. Again, a fairly nice area, near the bikepath down towards Kenilworth, some fields and the sports pitches. The building work up that end looks pretty likely to finish before term starts. I'd say Tocil is probably better, but it's pretty marginal.
Accessibility: Neither is great, with lots of narrow corridors and doors everywhere, but Cryfield is definitely worse, with loads of staircases in the middle of long, narrow corridors and such. Tocil's floors are at least all on the flat with no steps, and the corridors are fairly short.