Not really sure how many welding supply shops are around you, but as long as the hydrotest is current, you can probably find a place to swap out the tank. After that, you can find the cheapest refill place around you for the following 5 years. If you're lucky they're the same place.
I've had 2 Milwaukee regulators and no trouble keeping the bubble count standard. The troubles I've heard from people mostly regard keeping it standard at very low outputs (1bps or under, maybe). Even then, you can always switch out the needle valve for something higher quality.
You can also run a CO2 line as far as you'd like, though if it's more than a few feet, I'd probably put the needle valve and a bubble counter inline at the tank.