3rdGen- Down here everybody buys the 5 year. I think all the inconsistincies( not sure that is right) that youve been seeing will go away with the vac. You have to have just the right conditions for gravity flow and every little thing seems to affect it but with the vac its just not that way. With my stuff if its over 32 degrees the sap runs period. If you have the right conditions it runs even more but none the less it always runs. My neighbor went to vac after he saw what I did and he bought a small ring pump, gas job, and hooked it to his existing setup. The tube had been run pretty much right for vac. He stuck the pump on it and it performs pretty close to what mine is. The tubing is several years old, including the drops, and he just uses the new adapters every year so he has new plastic and it performs real good. I dont think it does quite as good as mine becouse I can leave my pump on all the time but it doesnt miss my numbers by much Id say. I think the recipe is high vac, never shut the pump off if you can, new plastic, properly installed line. Thats the combination Im going with. I would have made a lot more syrup this year if I could have single passed large volumes of sap through the ro at the end of the season I think. I think what I missed would have paid for my new ro but the bottom line is I can only afford to buy so much stuff per year and thats that. Im super happy with the season and next year Im going to work hard to do an even better job! Theron