high mileage oil weight?

No, I'm not experiencing anything that would make me want to change oils except for the price! I thought I read somewhere that changing to a 10w-30 might be beneficial in higher mileage vehicles so I figure I would ask and get some feedback before I just changed without reason. Pennzoil UP is more expensive, and harder to find so I thought about switching to mobile one HM, they say its for over 75k miles. I'm just looking to prevent any problems and save a little money. Ive been doing some reading and it seems switching to 10w-30 may not be the best option if I don't see a need to but I figure i would switch to a high mileage synthetic as a preventative measure since they are all listed for vehicles over 75k and Pennzoil doesn't have a full synthetic HM, and they're more expensive. I am thinking about trying Mobile One HM 5w-30 and sticking with that.

Thanks for the input. I typically buy my oil from Pep Boys Website (even though I wont take my truck to their store) because they are always offering coupons and promos every couple of months and I usually get a good deal if I buy my oil in advance. Right now they have 25% off $50 or more. I just bought 6 qts Mobile 1 HM Synthetic and a mobile 1 oil filter for $58 w/ free shipping! Hard to beat that. I just check their website every couple of weeks for a promo and it usually pays off.