Both Very Hard and Survival have the same damage modifiers. Enemies do double damage and you do half damage.
Survival's differences are less health regen from anything that provides it and huge enemy HP pools. Supermutants are especially dumb. It's not hard, it's annoying. The enemies on Very Hard can kill you just as fast, yet aren't completely ridiculous.
It did require me to plan my build a little tighter, get a serious amount of resources backing me by really delving into the Settlement game, so I had the best gear I could each level, and I'm using chems extensively (with the Chem Resistant perk) for the first time ever in a Fallout. You definitely need to work to maximize damage, as you have to kill things fast enough that they are not able to do the same to you. It's not just a matter of tanking it all. Things aren't immortal, though, and go down when put real effort into it.
All in all, though, the things that I feel should be tough are (Radscorpions, high end Supermutants) and I still chew through and spit out chumps like the average Raider. Gunners actually feel like the step up and above raiders that they're meant to be, as the gear and their higher DRs from having combat armor start to really show, as does their higher damage weaponry like Plasma. My power armor, for the first time isn't just 'Military Paint' on my X-01, and I'm putting the Bonus Energy Resist paint jobs onto it as I'm running into so much plasma and laser fire that it was actually cutting me up pretty badly.
Oh, and pipe weapons truly are garbage at that difficulty. Don't even bother. I use .38 ammo as a secondary stash of caps. "So, Kleo, here's 1400 .38 rounds, give me those five fusion cores..." Stick with the 10mm until you get something better.
That's just my opinion, though. As I mentioned before, I also made the environmental effects meaner on myself, just to add that much more to it.
The benefits of Very Hard -
Tons of Legendaries that give you a lot of shots at generated loot ( a lot will be crap, but there's enough that some will be very good)
Tons of consumables in containers (seriously, I only received a fraction of this amount on other difficultes)
Luck Based Scrounging Perks become even more rewarding. (I was getting more ammo than usual before, now I'm pulling between 45-75 rounds of random stuff out of an ammo box - and Fusion Cores are considered ammo).
Tons of gear in general (enemies have better gear? That means you will too once you kill them. I think I had a Combat Shotgun and Combat Rifle with ammo for both by level 8-10 or so)