When I did a couple of endurance rides, Folks would try hard to get me to use breeches and other fancy riding pants.  Offering to loan me al kinds of stuff.

I personally don't find denim jeans uncomforatable.  Only once or twice in all my years have I had any problems. Once was on a 50 mile endurance ride, My pants got wet and the wet pants rubbed a sore on the inside of both calves. I could have prevented this by wearing some half chaps or staying dry.

If there is a chance I'll get wet, I put on shotgun chaps.  If the risk isn't to great or the temps are warmer, I use Chinks. And the half chaps work great if I just need some protection below the knee.  We ride a lot of miles in all kinds of weather and just wear jeans.

What about boot cut riding pants instead of breeches??

Look more like pants---     I sent you a PM

I suggest he just go for a few rides.  If he starts getting rubs, then look for a solution to those problem areas.  Yes there are lots of guys who do wear breeches and seem to enjoy them. But I can show you a lot of pictures of cowboys working cows off horses in Jeans.  And I'll bet you won't see any breeches at any rodeo you attend.  Of course cowboys roping calves at a rodeo, don't sit on that horse for 25 miles in an afternoon either.

We put a lot of long miles on horses wearing jeans and some sort of chap/chinks.  Works for us.

If you look close, everyone of these guys is wearing jeans.

I think you can see from the photos I've posted that we are not in very hot weather here.

I live in Fl also. My hubby wears jeans with half chaps with no apparent issues...Check out Ariat's Terrain Half Chaps. I wear these and they are much cooler than regular leather and wear extremely well. They are made of a mix of leather and a mesh material.

Sometimes, you can find riding pants made of denim. My hubby had some of these but they wore out and he just went to regular jeans. Some wear panty hose under the jeans but that won't solve a riding up problem and I would consider it a bit of warm solution. I say, let him be comfortable and wear whatever works for him. You could possibly get some elastic straps that were meant to hold jodphurs from riding up. They clip to the bottom of the pants and go under the boot. That might also do the trick for him. http://www.legacytack.com/p/10477/Jodphur%20Clips.html

 I just got 3 pair of CINCH jeans the lady at the western store said they were great for riding and they have been so far I have always worn levis but I like the cinch jeans better. the seems dont bother the inside of your thigh and they are roomy in the thigh and but area. They are several labels to choose from I tried on all of them and liked the white label the best.

pantyhose under jeans brings back a wonderful memory. 

 I used to help wrangle on some riding holidays in Wy and they would tell the men to bring pantyhose to wear under their jeans. Two of the guys had their luggage lost, so we had to stop at Wal-Mart so they could replace some essential items - some of which were pantyhose  We got a kick out of figuring out what size these guys needed (Queen) and they said they came in quite handy during the week. They were all 6' and nicely built.

The last day of the ride, 3 of them modeled their pantyhose for the women and the only other thing they were wearing was underwear, boots, and cowboy hats!!  That image will be stuck in my mind forever (and they were mighty fine looking men!  sigh.... 

Dunoir, That's hysterical!! Thanks for the vision!

Panty hose  Now, they could present a problem when you have to go to the bathroom, I mean if you a guy.  I'm just saying!!!

Rose, CK wants to know what s.o. stands for. 

SO=Significant Other.

Knew a guy years ago who always wore pantyhose when he went hunting. Swore they worked better than long johns-just as warm and not as bulky.

Cowbut cut Wranglers, long enough that they stack quite a bit just standing in your boots, also, excessive rubbing can be a sign that your legs are not quiet enough, just a thought...

we have ridden long distances day after day, moving cattle from winter range to summer pasture......no rubs ...

 We have found that cotton (jeans) is cooler than synthetics....even with chinks for the brush..

I have always worn some type of denim jeans.  I like Wrangler better than most.  I will agree chaps make a big difference in the cold and rain,  But tend to find myself just in jeans in the summer.

I have alwas wanted to try the fleece lined jeans.  Good to hear they are comfortable.  I also like the long johns under jeans in the winter with chaps.

Painted horse - there are some quality eats going on in those photos LOL