I am looking to get a new collar/collars. I have a sportdog 1200 2 collar system. I would like to get tri tronics, but there is several different models. Tri-Tronics Pro 100 G2 EXP, 70 G2, 90 G2, 500 G2, Upland, Fly away and so on. Which one would be the best for me. (not rich) The 70 or 90 is the price I like but would it be suit me? I am new to field trialing and hunt my dogs. I do want to be competitive in field trialing so I would like the best for my budget.