Whether it’s suitable depends on; how strong you are, how far you’re cycling each day, how much you’re carrying and how hilly the landscape is. Also, if you’re going somewhere really windy, you should consider that.
It’s easy to be all macho about lowest gearing but if you’re putting in long, hilly, loaded days, day in week out, you’ll need low gears. If it’s just weekend credit card touring, you can get away with murder.
Half way through a ‘significant tour’ with a massive headwind and a 30 mile 9% climb ahead, you’ll be glad you went lower. My ‘standard’ lowest is 24/32 and my lowest 22/34, I do run a 20/34 on the tandem for really beastly terrain 🙂