I think what the disclaimer say about "big amount of transactions" means the number of transactions you make day by day.
the number of coins you transfer in one single transaction would not be an issue.
On official dogesite, they recommend two online wallets: dogeapi & moolah
anyone got opinions on these two or maybe please give link to a thread discussing them
Im sorry if my post doesnt actually relate to the topic of this thread, I'll edit/delete my post if needed
I think dogeapi just announced that they were shutting down. A good online wallet is https://block.io/ in my opinion.