I have never used either, but it is my understanding that you are looking at opposite ends of the IVC market.
I believe that backwoods are the more affordable and LSG are basically top of the market.
I assume it doesn't make a huge difference in performance and good Q can be made on either. Have to believe that the LSG will last longer.
Not sure where you are located, but it should not take too long for a good used cabinet to come to market. Check Facebook used bbq groups, craigslist, offer up, etc.
It took me less than a month to find a used Humphrey's Pint in So. Cal.