Unless you need something as durable as a tank, I would look at Walmart and target for really inexpensive options.
I picked mine up at Walmart for $30.
The biggest difference between a $100 bag and a $200 bag is going to be how well the sides of the bag keep form and don't sag when it's not beeping full.
That will make it extremely hard to roll consistently.
And make sure what ever bag you get has roller blade wheels and not a crappy plastic substitute.
If you really want a paintball brand bag, look for a used one.
Eclipse or Empire is what I would recommend
#9 of 19 PBX LV1
Lime Spire 260
Lime PBX 68/4500 a tank w/Ninja Reg
for the #1 field in Chicagoland
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