The .243 Win is plenty sufficient for deer size game if using the proper bullets. The better bullet weights are in the 95+ gr weights. I've found that bullets with a sectional density of around .250 are best on deer size game. The .243 Wind has the advantage of longer game getting shots compared to the 30-30, if the hunter is capable of shooting at such ranges accurately. The 30-30 round uses bullets normally in the 170 gr range and thus has higher sectional density, which is probably why it has such a good reputation for a game getter. Not to detract from rifles that are light, sufficiently accurate, and fast target acquisition chambered for this venerable round. Either would be a fine choice for new hunters as ammo is reasonable and easy to find. Both are excellent deer rounds. I have both and use both in Alaska on deer size game, such as goat, deer, average black bear, caribou, and the occasional sheep. The 30-30 is a T/C old style single shot, so pointed bullets can be used to best effect at long range. In no way am I to disparage levers in 30-30 as they are effective too. I agree with earlier posts to find the rifle that fits the hunter and either cartridge will be fine for deer hunting.