Ultimately they are your jeans so you can do whatever you want LOL

But yeah I agree with LaDoozie, I prefer not to alter mine, I just cuff them, but I am lucky because I dont have to cuff a great deal because the smaller waist sizes are much shorter in the leg to start with. If you do get them altered consider somewhere like Blue in Green, a specialist denim retailer who has older Union machines which can alter the hem to length but retain the correct chainstitch. A good seamstress can even shorten the leg but retain the original length by not actually cutting them, just sewing them inside the leg of the jeans to create a new hem. if you then want to undo the new hem stitching the original length will be returned. For some the resale value of the jeans might be reduced by altering them, but realistically you bought them for you to wear, and at the end of the day so thats the main thing. Better to be altered than to look ridiculous by being vasty too long for you I guess. You could also tape the bottom of the leg up inside itself as well as an option.