It will be quiet interesting if you'll use Bitcoin & Ethereum at the same time as a payment method. For faster transaction if it's peer-to-peer or third-party-programs; you might wanna recommend to use Ethereum for quick transaction. In the other hand, Bitcoin is kinda sluggish for blockchain transaction.
Who says Bitcoin is a bit slow for blockchain transactions? even at this time Ethereum transactions that have a lot of pending unless someone uses a slightly higher fee when making a transaction so that the transaction can be successful more quickly.
actually everything is on the fee constraints that are prepared for all transactions. ethereum and bitcoin are actually the same transaction speed depending on the fees provided to make transactions. Most people are looking for every transaction with an affordable fee which of course will have the risk of being slow for the transaction. want bitcoin or ethereum has no effect in the speed of transactions that make fast or slow can be ascertained because the fee is prepared only, to be able to quickly the easiest is to prepare a fee above the average requested can be ascertained will be completed quickly the transaction.