You can't go wrong with either of those options.
For railed handguards you typically need to add covers to protect your hand and the rails themselves. Some shooters don't want any extra weight/bulk. In the grand scheme I think it's a wash.
For tubular units adding, moving, removing rail sections can be a PITA unless you take off the handguard each time.
The heat issue was addressed above. Generally for heat mitigation it's tough to beat the old school insulated handguard pieces on non-free floated rifles.
My advice is to grope the shit out of each style at a gun store and decide which you prefer. I prefer tubular but if I use a rifle with rails I don't lose any sleep over it.
Before you suggest that licensing, background checks, or other restrictions for the 2nd Amendment are reasonable... Apply those same ideas to the 1st and 4th Amendments. Then tell me how reasonable they are.
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