The best would be from a mining pool operators confirming this.
If no solid evidence to prove the legitimacy of these two paid accelerators, no one should use both of them if you want to avoid scam.
The first: Free and Paid service.
https://www.bitcoinjumper[dot]com/
With paid submission your transaction will be manually added to be confirmed by one of our partner mining nodes. The fee for this special inclusion into one of the next blocks means you'll need to pay above the current miner processing rate for BTC/kB. This miner fee is automatically calculated for you to make sure you only pay what is needed.
The site also offer free accelerator, but obviously it can not work, just like other accelerators that should be avoided as they are doing nothing than rebroadcasting the transaction:
With free submission you only need to submit it once and our app will resubmit your transaction every 15 minutes to the broadcast nodes automatically until confirmed. This is what makes our free BTC accelerator so powerful and user friendly.
The Second: Paid service.
https://btcnitro[dot]com/
Bitcoin transaction stuck or slow waiting for confirmation? This can happen with the network is very busy or if you used a low mining fee.
BTC Nitro sends your transaction to our network of mining partners who will include it in the next block they mine.
I too or anyone can come up with such idea and use it to scam people. Are they not scam sites? The bitcoin transaction accelerators that we should believe are the ones owned by mining pool like ViaBTC accelerator.
Mate, you will be reported to the admins. I was just posting an answer on a question of another member with my personal experience. No need to throw around with bad reviews!