UKH

I blew up my rear shock on the weekend, a fox float triad, it squirted the oil out through the adjustment dials. 

Question is, I can get a replacement on offer for at the moment for just under £110, or pay £90 + any extra unknown broken parts for a service.

What would you do? 

New...

The very fact you've managed to break it by "squirting oil out the adjustment dials" would indicate there'll be some costs in repair. So defo replace. I'd be more asking myself do i need a burlier shock if i've teetotalled one under normal use?

Blowing an air shock is not an unusual thing.

Take the opportunity to see if you can upgrade (also look at Rock shox units etc). 

If you can get a good deal, sell the blown shock on ebay 'for spares' as some people can fix themselves.