Ok, boots tend to last about 1-2 yrs from what I've seen on the threads about boots and my own experience. So, the boot pants analogy makes some sense. Making the leap from regular wear to professional grade workwear is always tough. I went from $20 chainsaw pants to the $80 then on to the $120 regular forestry pants. They lasted about a year but would always blow out their crotches. Often in less than a year so I'd take them to a tailor to be repaired. After a while I grew tired of wearing pants that weren't designed for the job of climbing.
So, I broke down and bought my first pair of Pfanner gladiators with chainsaw protection. I couldn't go without the protection as it felt, for me, weird to climb without them. They were great, comfortable, moving with me no matter where I went in the tree. They stood up to daily usage. I work usually 6 days/wk so they got their fair share of abuse. Oh, I worried about them getting ripped up on the first day or week of use but, by that logic I'd be buying cheap rope, boots and everything else that could get whacked on the first day. However, when they did get a nick from a branch or handsaw, they still outlasted cheaper materials. I took these to a tailor and extended their life to 3 yrs. I bought two more pairs over that time, one each year to reduce the amount of usage per pair. I tried the vented version which doesn't have the full wrap of protective material around the calf but were significantly cooler in the summer. Simply adding some long underwear in the winter makes up the difference.
Last year I bought the Francitel pants as an alternative, based on Familytree's glowing review, and have found them to be a great pant. They are lighter than the Pfanners and just as comfortable, also have lasted as long. despite the few nicks in them they look good. The material is durable and made to withstand the wear and tear of our business. Now on that point, is the more important one. The point of protection. I'm in a position to speak with first hand knowledge about the impact of a decision to not adhere to a industry standard.
When you look at the cost of something that relates to your protection then weigh the cost of the accident that it's meant to protect you from. While I've been in the hospital I've heard plenty of stories from the staff here of the chainsaw accident victims they've seen. Amateurs and professionals alike, are victims. The average cost of a chainsaw cut is $7500 in medical bills. Then there's the lost income which, under WC rules could be at least 30% but, if you make over $21/hr will be even higher since there's a cap on what they'll pay out. So, now the figure is rising toward $10K. Let's use the same analogy you've used. How many pairs of pants would that equate to? 30? Hmmmmm......
Look more professional and have some peace of mind that you're not going to end up being one of the 10,000 professionals that cut themselves with a chainsaw. Oh and the leg is one of the primary sites for cuts.
Sorry for the long response.