I ordered the 4" one from them about a month ago for a 300BO I was putting together. I didn't have any problems with them.
Sent from my Pixel 3a XL using Tapatalk
That would work, because when you find that the rail becomes the devils tent stake, you will want to switch to something that sheds heat a bit better. However, since its cheap, you won't be out much and can always cut it down.
ETA- I thought something smelled Chinesey on that site, even the rail names are Chinese!!!!
The plan in the end is to use high heat resistant carbon fiber, but this will do just fine for testing purposes. Just for context, the high heat CF tubes are about 500 to 1,000 dollars each for the lengths and shell thicknesses that would be applicable to this application. Little bit pricy for prototyping.