GD, If you do Bolton make sure you have a lot more time than you would for any other tri for the setup and collection, T1 and T2 and the finish are 10-15 miles apart and the traffic can be a pain. Someone flipped a caravan on the M61 on Saturday that caused havoc. Outlaw is a lot less expensive.
FWIW I used the Virgin Cyclone as a training ride/tt it's 104 miles but with 8000 ft of climbs, I'd post the course but I wanderded off it by mistake this year.
https://virginmoneycyclone.co.uk/CycloneChallenge.asp?ShowPage=549 .
This one was the toughest ride I did in training,
http://connect.garmin.com/activity/189943090 . 132 miles/10000 ft
Not many places in the UK with roads at 2000 ft.
I did the Kielder marathon last year too. So with Kielder and the tough ride under my belt I felt confident I would finish so mentally I was ready, I had no idea what time I would do though. I gave Mrs Gere some estimates and I was bang on until the marathon which I'd hoped to do better in. But still happy with my time.
HTH.