Growing Indeterminate Tomatoes in Grow Bags

[garyc1234]

I've been thinking of growing indeterminate tomatoes in grow bags. I've seen others on this site use grow bags, so I'm thinking of trying it out myself. I have a bunch of tomatoes in containers already, but I've basically run out of containers, and I still have some more plants that needed to be potted up to their final container. Grow bags seem like a quick and cheap solution since I don't have time to build any more Earthtainers this year, and even 5 gal SW containers from Home Depot buckets would take time to make. Here are some questions I had. (I did search this site for some info, so apologies if this was already discussed in another thread.)

(1) What mix do you put in grow bags? For containers, I am used to using potting mix (Miracle Grow w/o Moisture Control). However, I am reading in some places that for grow bags, I should be using potting soil instead of potting mix because the bag already provides plenty of aeration for the soil. Is this correct?

(2) How long do grow bags last? I know every grow bag may be different. I am using the VIVOSUN 5-Pack 15 Gallons Fabric Pots Grow Bags that I purchased from Amazon last night. However, if the grow bags only last one growing season, that is adding ~$6 to the cost for every tomato plant every year. Then plastic containers may be a better long term solution.

(3) Anything else different about growing in grow bags rather than regular containers? Still a circle of Tomatotone at the top, and I assume you can still use a cage if the grow bag is large enough? I am using 15 gallon grow bags. I assume this should be big enough for most indeterminate tomatoes? Thanks!