It depends what you mean by ‘good value’; these’s not much point buying a cheapo one if it breaks up. Your friend will need one with at least 65 and ideally 85 litres volume if it’s to be his only pack. There are versions that have a handle on the side so they can be carried like a regular suitcase, and/or the straps can fold in so it looks like a suitcase (which can be handy in snotty hotels that don’t like backpackers) Don’t buy one with lots of external pockets as he’ll need a lock for each one. I’ve a Lowe Alpine and one padlock can lock both the main compartment zip and the zip on the top compartment at the same time. You could try the Great Outdoors (great range but pricey), the Lowe Alpine shop in Temple Bar (is this now North Face?), or (my favourite) Outdoor Adventures in Liffey St.