make no doubts, foch155 is probably one of the best tier 10 TDs and can 1 clip almost every single tank in the game. Everything leading up to it is kinda painful. (Tier 8 and 9 can be fun though, or so I've heard)
The british TD line is ... interesting. But also painful. I'm slogging through the AT2 and it's just not an impact tank. Lost count of the number of games I've lost because I could not get to a furball in time. Or was outmanuvered by semi-good players. Or got my ass handed to me by a KV-1 (packed 20 gold rounds just for them).
The rest of the line are all also heavy armor slow tanks.
It's like driving the T95 for tier 5, 6, 7, 8 and 9 to get to the 183. Though the tortoise is pretty fantastic and so's the AT-7, but everything in the line are slow moving tanks that play like the T95.