Welcome to TBN.
You don't say what you need to do with the tractor, but lets just say you've decided that at least 28 HP will do what you need.
The CK30 has a little higher HP, offers telescoping hitch arms and stabilizers where the Massey offers fixed arms and turnbuckle sway chains.
The CK30 will be much easier to hook up implements to.
If you want a mid mount mower (MMM), the Massey would be the better choice as they list the mid and rear PTOs as standard, the CK30 mid PTO is an option, and the MMM is not ready yet, last I heard.
You also don't say whether you're quote was for the 1428 with HST or manual transmission. The HST (like an automatic) is usually a bit higher than the shuttle shift manual tractors.
The CK30 should quote out with FEL from between about $14,500 and $15,500 depending on the area in which you're looking. Shipping and operating costs can be much different in some parts of the country, thus the pricing differences.
Find the one that's comfortable for you, making sure you're comparing feature for feature, and what's extra as an option.
Another plus for the CK30 is the 50 amp alternator, in case you want to add a lot of extra lighting, and it weighs a good bit more than the Massey which helps with putting the power to the ground. Also, the CK30's hydraulic flow is higher, making for faster loader operation.
The two tractors are not really comparable, but close enough to compare. It's up to you as to which is right for you, and I don't think you'd regreat either of them.
John